sympy/sympy — pull request #1816 by skirpichev (2013-02-21 22:13:15+00:00)
Title: Fix for #3626

Function._eval_series() does naive and completely wrong prediction for number of taylor terms if the argument of function is non-atomic.

Simple test:
```
In [1]: sin(sqrt(x))._eval_nseries(x, 3, None)
Out[1]:
3/2
___ x ⎛ 3⎞
╲╱ x - ──── + O⎝x ⎠
6
```